Project Summary An important public policy challenge in the coming decade is how to provide patient- and family-centered care for an increasing number of Americans afflicted with Alzheimer's Disease and Related Dementias (ADRD). The proposed research team has documented that, despite family preferences for care that maximizes comfort, patients often receive burdensome treatments and unnecessary health care transitions in the last days of life. A recent publication by Teno, Gozalo, and colleagues in JAMA IM noted that the use of mechanical ventilation in persons with advanced dementia has been increasing over the past decade. In the preliminary study for this application, we document the increase use of non-invasive ventilation from only 900 admissions in 2006 to 2075 admissions in 2013. The use of non-invasive ventilation (NIV) has not been studied in persons with advanced ADRD. The value of mechanical ventilation in a population of ADRD patients is questionable based on high 1-year mortality and that most families prefer comfort-maximizing care. There is a lack of authoritative outcome data on the effectiveness of invasive mechanical ventilation in ADRD patients. Our previous studies of the comparative effectiveness of feeding tubes in persons with advanced dementia contributed to AMDA, AGS, and AAHPM recommendations in the ABIM Choosing Wisely Program to not use feeding tubes but offer hand feeding. The overriding objective of this proposal is to provide authoritative, actionable national information on the outcomes of invasive mechanical ventilation (IMV) and non-invasive ventilation (NIV) in persons with advanced dementia by addressing the following questions: 1) What are the temporal trends and individual, hospital, nursing home, and market characteristics associated with the use of the IMV and NIV in persons with advanced dementia between 2000 and 2019?, 2) What is the comparative effectiveness of IMV and/or NIV in the care of hospitalized persons with advanced ADRD using cross-temporal difference-in- difference propensity matching?, and 3) Can a prognostic model be created with sufficient discrimination and calibration to provide actionable information to health care professionals and surrogate decision makers? Our proposed research will be the first national study of IMV and NIV in person with advanced ADRD. Furthermore, it will capitalize on rich clinical data from MDS assessments to create prospective cohorts of persons with advanced ADRD, employ novel cross-temporal propensity matching methods, and examine the growth of IMV and/or NIV, enhancing our ability to draw causal inferences from an observational study. Knowledge gained from this research will provide important information regarding the use of IMV and/or NIV in the care of persons with advanced ADRD with the ultimate goal of delivering high value-based care that respects patients' rights to make informed choices about their medical care.